In recent years, although a high-performance thermoelectric material in which a superlattice structure is utilized has been developed, the material is generally capable of being manufactured only in the form of a thin film (10 nm to 10 μm) on a substrate, resulting in difficulty in being produced as a thermoelectric module commonly used. Such difficulty is caused for the reason that manufacture of a thermoelectric module requires a thermoelectric material of approximately 1 mm square.